Method of polymerizing vinyl compounds



Patenied'sept, 16, 1930 l I UNITED, STATES,

PATENT OFFICE CHARLES o. YOUNG AND STUART 1). DOUGLAS, or CHARLESTON,wns'r vmemm, AS-

SIGNORS T ennmnn & cannon CHEMICALS CORPORATION, A oomaoaa'rron or NEWYORK or touse a combination of these measures.

Several substances have been used as-catalysts but powerful oxidizingagents likehydrogen peroxide and benzoyl peroxide have met with thegreatest favor where :vinyl compounds were involved.

j We have found. that P-b:(G H is an excellent polymerizing andcondensing catalyst, especially in the polymerization of vinyl chloride,vinyl acetate,

andmixtures of these compounds. -The'poly-.

- mers formed in the presence of tetraethyl lead are found to be'lessafi'ected by heat and exposure,'and hence are more useful than resinsmade by othermethodS. A

Films containing vinyl resins prepared by prior methods, have been foundto exhibit an objectionable tendency to disintegrate upon prolongedexposure, andto darken when heated. These tendenciesare'especiallypronounced when the films are in Contact with metal, and it has beenassumed that corrosion of the underlying metal by acid developed in theresin isin some measure responsible for the deterioration of the film."

Films containing resins prepared with tetraethyl lead are more stable incontact with metals. To explain this greater stability we ofl'er'thetheory that films prepared withtetraethyl lead, an oxlygen-freecompound, contain less acid, and ave less tendency to produce acid thanthe resins heretofore prepared with oxidizing catalysts. It is posleadtetraethyl METHOD OF IlE'OLYMERIZING VII INYL COMPOUNDS Applicationfiled December a7, 1928; SeriaFNo. $28,846

that the invention is not to be restricted by any theory advanced. Thefollowing examples will serve to illu's trate the invent1on:

1 Example I 1750 parts of vinyl chloride, 1750 parts of vinyl acetateand 70 parts of lead ethyl are added to 1500 parts of acetone in apressure autoclave, preferably made of steel and lined with tin or leadand heated at 100 C. for 24 hours. A tacky, white viscous resin solutionis formed. U

Erample I I I 7.0 parts of viniy and heated for 20 hours in a suitableautoclave; at 80 C. A white, viscous gelatinous. resin solution isformed.

Ewamfle III 105 parts of vinyl acetate and 2 parts of lead ethyl areadded to parts of acetone and,

- with other catalgsts, and actinic light or other accelerating inplied.

' We claim 4 ILA method which comprises pol merizuence can of course beap- I l chlorideahidlxl parts of v ing vinyl compounds in the presenceof lead tetraethyl.

2.-A method of polymerizing vinyl comand heating the mixture.

In testimony whereof, we afiix our signatures;

7 CHARLES O. YGUNG. STUART D. DOUGLAS.

i si-ble,.however, that polymers prepared by our process difl'er fromPIIOIJGSjIIS 1n their mo-- Wlecular structure and 1t 1s to be understood,pounds which com rises mixing the com- .pound to be polymerized withlead tetraethyl,

